Mosquito & tick repellent

[cygnet7]

Every year I run into the same dilemma:  how to keep the noxious insects away without wallowing in toxic chemicals, If I am outside working in a particular location I can use a citronella lantern, but I am usually moving around from one place to another. In addition, I react badly to some essential oils, but haven't been able to narrow down which ones. *facepalm*
What can you all recommend that is effective and safe?